It is known that the illumination of a vehicle is subject to security relevant aspects and in particular has to indicate the light signals of the driver reliably, but as well the light signals marking the vehicle. In this connection there exist technical requirements with respect to the minimum and maximum illuminating power of the commonly used light signals such as flashing indicator, rear light, brake light, back-up light, rear fog light and so on, in order to be visible well during daylight and not to be excessively bright at night in order to not to blind other traffic participants. In particular, there exists a requirement to also provide the light signals in a well recognizable and visible way in a viewing direction lateral to the vehicle.
For this, as an example a classical and proven means has been to provide an additional doubling lamp each for the front and rear flashing indicator, which is arranged laterally on the body of the vehicle. Often such a second flashing indicator lamp is provided in a side mirror. This requires additional expenses with respect to material and mounting, by which additional costs arise and correspondingly the repairs and maintenance expenses are increased in addition. In some countries, such as the US, there exist traffic related regulations, which dictate a lateral visibility of tail lamps, flashing indicators and brake lamps, respectively. Many producers try to solve this problem without an additional lateral lamp in that they design the vehicle lamps in such a way, that these additionally also emit the respective light signals to the side and away from the vehicle. In the following a range of such solutions is presented.
Disclosed in DE 21 40 165 B2 is a reflector for motor vehicle lamps comprising within the same curved region at least two separated curved reflector planes, which are formed of rib-like partial plane supports which are arranged alternating adjacent to each other and form two different oriented concave reflectors. Each of the reflectors thereby has a discontinuous surface and therefore only directs a portion of the light into the intended direction, wherein the two emitting directions may only differ in a relatively small angle which has to be much smaller than 90°.
Disclosed in DE 90 01 659 U1 is a tail lamp of a motor vehicle in which the reflector for the flashing indicator extends across the entire width of the rear area of the light disc section for the flashing indicator and extends far into the lateral region of the light disc section. The reflector comprises regions which are occupied by triangular prism and cylindrical lenses which are arranged facing towards the light sources at the inner side of the reflector forming the outer shell of the tail lamp. Furthermore, disclosed is an additional intermediate light disc or an optical disk which is also occupied by lenses facing inside in the direction of the light source. Furthermore, the reflector is provided with ribs or grooves which serve as an optical light dispersion means. The regions between each of the functional areas of the reflector not used have roughened surfaces in order to separate the functional areas.
DE 10036 324 A1 shows a multi chamber lamp in which for increasing the brightness a rod- or strip-shaped fiber-optic light guide is arranged such that the light is deflected into the adjacent light disc sections, wherein the fiber-optic light guide comprises optical means which deflect the light into the desired light direction. The light disc is designed bell-shaped and has on its front side facing towards the light source optical means, particularly prism, which concentrate the light incident thereon and further other optical means, which disperse the light. In order to separate single functional light areas intermediate partial regions are made impervious to light, as for example also the fiber-optic light guide is made with a vapor deposited metal layer on the side opposing the light disc. The light disc is integrally designed with the optical means and serves as a colored filter or may comprise colored filters.
DE 10 2004 047 548 A1 discloses a tail lamp serving as a third brake lamp in the rear area of a vehicle in which the light disc for reasons of easier mounting is designed in two segments and is sealed against the body parts of the vehicle using gaskets. This is an additional lamp and therefore implies additional cost, wherein it moreover does not lead to an increase in lateral visibility.
Disclosed in DE 103 32 977 A1 is a tail lamp in which two illuminating coils are provided in a light source serving as a light bulb, whose light is separately supplied to two different functional areas by means of optical means such as fiber-optic light guides and lenses, for example to the brake light and the tail lamp. Fiber-optic light guides, prism and lenses are provided as an optical means. One or more fiber-optic light guides are provided for the one filament and the lens is pointed towards the second filament with its focus. This solution requires a specific light bulb comprising the two illuminating coils spaced from each other.
DE 103 61 488 A1 discloses a lamp for motor vehicles, which proposes to solve the heat problems of a lamp such as to arrange optical prism areas in the base part of the light source, in this case a light bulb, which deflect the incident light into the light outlet direction of the lamp. This way indeed a better light emitting efficiency reducing the heat losses is reached, but a specific broadening of the light outlet angle is not effectively reached.
Disclosed in DE 197 32 742 A1 is a preferably frontally positioned lamp installation of a motor vehicle in which for reasons of fulfilling regulations for lateral visibility of the light signals the reflector has a discontinuous region through which a portion of the light of the same light source may leave laterally. In this connection, the reflector plane is discontinuous and the light of the light source without being deflected directly leaves to the outside laterally through the cover disc, which on its inner side may comprise optical means such as lenses or prism for scattering the light. With this solution an additional reflector manufactured and mounted as an individual component is used, by which additional cost is generated.
DE 198 20 656 A1 discloses a multi chamber lamp for vehicles, which for the purpose of reducing the loss of light and for covering the inner parts of the lamp against visual access from the outside comprises non optical regions and covering regions in the intermediate light disc and the covering disc.
DE 198 60 669 A1 discloses a headlamp in which for the purpose of improved allocation of the low and high beam areas bezels are arranged in front of the light source and in which these bezels serve as reflectors on their back side, wherein the light reflected back is pointed at an additional reflector for the near area formed above.
DE 694 01 314 T2 proposes, essentially for reasons of design, to use light scattering elements made of a transparent plastic material comprising light reflecting metallic particle for laterally framing a vehicle lamp. Thereby indeed also the illuminating angle may be enlarged, but the attenuation of light due to light scattering may be too large, so that the brightness of a vehicle lamp may be afflicted.
EP 0 715 988 B1 and DE 695 12 614 T2 disclose a vehicle tail lamp in which a intermediate light disc, the reflector and the outer end casing comprise optical means such as prism and cylindrical concave lenses which are arranged in rows on the side facing the light source and facing in the direction towards the light source. Such additional optical means do not allow for to always, and not in each application, achieve the required broadening of the light outlet angle and thereby the required lateral visibility of the light signals.
Furthermore it is an requirement to form a vehicle illuminating device, in particular that of a passenger car, as compact as possible, so that it may be adapted to the desired external shape of the body of the passenger vehicle without, in doing so, requiring too much of the inner space of the vehicle which would be lost at the cost of a reduced volume of the trunk.